I have just created a new root site on SharePoint 2010. I enabled the SharePoint Server Publishing Features at the Site Collection level, and then also at the Site level. I then added some new reusable content items (one txt, one HTML)

When I edit a page, I can see the "Reusable Content" icon in the ribbon, but it is greyed out and says "This control is currently disabled".

Could this be because I am trying to edit the wrong kind of page? (I tried editing the site home page, and then tried creating a new page from scratch) or do I need to enable something else?